The regional Health Ministry told Itar-Tass that no new cases had been reported in three days.

Sixty-one people remained in hospitals in the area, and 95 had been discharged after treatment. The diagnosis has been confirmed in a total of 150 people with the other cases suspected.

Legionnaire’s disease is a respiratory illness caused by a bacterium that lives in wet environments, including air conditioning systems. It was first recognized after an outbreak among American Legion members attending a convention at a Philadelphia hotel.

Health officials are trying to determine the source of the infection.

Yekaterinburg is 1,000 miles east of Moscow on the far side of the Ural Mountains.